Method for the automatic configuration of communication relationships between communicaiton units situated in a packet-oriented communications network

ABSTRACT

In the inventive configuration of a communication relationship, a data packet comprising the respective address information of the communication unit is generated by at least one remote communication device or by at least one communication unit that is assigned to said device and is transmitted to a central communication device via a communication network. Said central communication device selects an assigned communication unit and generates a data packet, which comprises the respective address information of the selected communication unit, said data packet being transmitted to the remote communication device. The communication relationship between the addressed communication units is configured with the aid of the transmitted or exchanged address information via the communications network. The inventive method can be advantageously used during the initialization of a communications network, e.g. a booting of the system, as no communication with a management system (central or remote) is possible during this period.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the US National Stage of International ApplicationNo. PCT/DE2003/003898, filed Nov. 25, 2003 and claims the benefitthereof. The International Application claims the benefits of Germanapplication No. 10255159.6 filed Nov. 26, 2002, both applications areincorporated by reference herein in their entirety.

FIELD OF THE INVENTION

The invention relates to a method for the automatic configuration ofcommunication relationships between communication units situated in apacket-oriented communications network.

SUMMARY OF THE INVENTION

In the interests of optimizing current communications networks, inparticular broadband subscriber access networks (also called accessnetworks), a large number of subscribers are to be guaranteed low-costaccess to both narrowband and broadband services—e.g. video-on-demand.In the course of this optimization, the technological and economicalcost of implementing network devices that can be situated in currentcommunications networks may be reduced by using technologies that havenot been specifically developed for broadband subscriber accessnetworks, but for mass markets (e.g. personal computers). An example ofsuch a widespread and correspondingly further developed technology isthe “Ethernet”, which has been standardized according to IEEE standard802.3 and which provides a frame-oriented or packet-oriented andconnectionless transmission method. In network devices that can besituated in current communications networks, such as—forexample—multiplex devices, it is known for data cells, for example thoseconfigured according to asynchronous transfer mode (ATM)—also called ATMcells—as well as time-slot-oriented information (e.g. TDM or PCMstructures, Pulse Code Modulation) to be switched, via an Ethernetsituated locally in the network device, between remote subscriber linemodules situated in the network device and at least one central unit ormodule having central functions. The Ethernet may be used both as a“wiring” or “backplane” in a card rack for bridging short distances, andas a comprehensive communications network for bridging larger distances.

In the transition from traditional, circuit-switching ortime-slot-oriented communications networks to packet-orientedcommunications networks, particularly on communications networksaccording to IEEE standard 802.3, the change in transmission method alsoentails changes in the addressing and configuration of the systemcomponents involved. The following system structure is frequently usedin current communications networks:

-   -   a central module—hereinafter also called a central communication        device—with a plurality of assigned communication units        providing Ethernet interfaces, for example—hereinafter also        called transformer modules—which are connected via a central        switching device—e.g. Ethernet switch—to a packet-oriented        communications network—e.g. Ethernet,    -   a plurality of remote modules—hereinafter also called remote        communication devices—each of which likewise incorporates at        least one communication unit providing an Ethernet interface—a        transformer module—in which at least one communication unit is        connected via a switching device—in this case an Ethernet        switch—to the communications network, and—via said        communications network—to the central communication device.

In the system structure described above, the object is to facilitate afunctional startup of the arrangement or system—i.e. to boot it up—insuch a way that a logical point-to-point connection is set up betweencommunication units or transformer modules assigned in each case to aremote module and to the central module.

A conventional solution option consists in setting up the individualconfiguration of the respective point-to-point connections via thecommunications network by means of local management consoles that can beconnected to the communication devices. However, in a system covering alarge geographical area, with many remote communication devices, thiscannot be done by network operators due to the increased cost. Thealternative option of having a fixed configuration is likewise notpossible, since the assignment is to be effected dynamically.

The object of the invention is to improve the configuration ofcommunication relationships between central and remote communicationdevices situated in a communications network, such that no interactionwith a central management system is necessary. This object is achievedby the claims.

In the inventive method, communication relationships are configuredbetween communication units situated in a packet-oriented communicationsnetwork, assigned to at least one remote and one central communicationdevice, and in each case having communications-network-specific addressinformation. The main aspect of the method according to the inventionconsists in that a data packet comprising the respective addressinformation of the communication unit is generated by at least oneremote communication device or by at least one communication unit thatis assigned to said device and is transmitted to the centralcommunication device via the communications network. Said centralcommunication device identifies the address information contained in theincoming data packet, selects at least one communication unit assignedto the central communication device, and assigns the identified addressinformation to the selected communication unit. Furthermore, saidcentral communication device—or at least one selected communicationunit—generates at least one data packet which comprises the respectiveaddress information of the selected communication unit, and transmitssaid data packet to the remote communication device via thecommunications network. The communication relationship between theaddressed communication units is configured via the communicationsnetwork with the aid of the address information transmitted to thecentral and remote communication device.

The main advantage of the inventive method consists in that nomanagement system (central or remote) is required for the setting up orconfiguration of communication relationships between communicationunits—e.g. interface units or transformer modules—situated in acommunications network. The inventive method can therefore be usedduring the initialization of a communications network, e.g.—a systembooting, as no communication with a central management system ispossible during this period.

Only after these communication relationships have been set up accordingto the inventive method is it possible, for example, for the managementsystem to communicate via the communications network via thecommunication relationships that have been set up. The inventive methodmakes it possible, at the earliest possible stage during systeminitialization, for the communication units or modules involved in acommunication relationship that is to be set up, to be notified of therespective reciprocal communications-network-specific addressinformation—also called MAC addresses—at runtime, thus facilitating arandom assignment for the point-to-point connections.

The packet-oriented communications network is advantageously configuredaccording to the IEEE standard 802.3. Such communications networks thatare based on Ethernet technology are designed for the mass market inlocal networks (LANs) and are therefore low-cost. With the aid ofEthernet technology, therefore, internally situated communicationsnetworks can be used, for example locally in a network device, ascost—effective wiring of—for example—central and remote modules(“backplane”).

Other advantageous embodiments of the inventive method and acommunication arrangement for implementing the inventive method aredescribed in the dependent claims.

The inventive method is described in greater detail below with the helpof two drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a communication arrangement, situated in a communicationsnetwork, for implementing the inventive method, and

FIG. 2 shows an alternative development version of the communicationarrangement shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a block circuit diagram showing a network device NE that issituated in a subscriber access network or access network ACCESS andconfigured as a multiplex device, and in which the respectivesubscribers—not shown—are connected to a higher-level communicationsnetwork OKN—for example an ISDN communications network—via a pluralityof remote modules DBG . . . k situated in the network device NE and viaa plurality of subscriber accesses TA or subscriber access lines. An“internal”, packet-oriented communications network EN—hereinafter alsocalled “Ethernet”—which is configured according to IEEE standard 802.3,and via which the respective remote modules DBG1 . . . k—hereinafteralso called remote communication devices—are connected to a centralmodule ZBG—hereinafter also called a central communication device—issituated in the network device NE. The remote communication devices DBG1. . . k and the central communication device ZBG each have a switchingdevice SW—hereinafter called the Ethernet switch—which has been adaptedto the transmission technology of the communications network EN, wherebysaid communications devices DBG1 . . . k, ZBG are connected to thepacket-oriented communications network EN via a connection port of theEthernet switch SW and a connection AD, AZ of the respectivecommunication device DBG1 . . . k, ZBG, said connection being providedfor this purpose.

In this exemplary embodiment, each remote communication device DBG1 . .. k has a communication unit KE represented by a transformer module KE.Each transformer module KE implementing the subscriber accessincorporates transformation functions for the transition between—forexample—time-slot-oriented transmission technology that is implementedon the subscriber access line, and packet-oriented transmissiontechnology—in this case TCM/Ethernet—that is implemented in thecommunications network. Each transformer module KE is connected to theEthernet switch SW assigned in the remote communication device DBG1 . .. k. It should be noted that each remote communication device DBG1 . . .k may comprise a plurality of such transformer modules or communicationunits KE.

It should also be noted, in the event that only one communication unitKE is assigned to the remote communication device DBG1 . . . k, that theremote communication device DBG1 . . . k and the assigned communicationunit may be logically combined, in other words may be regarded as anidentical or logically related unit.

Furthermore, a plurality of transformer modules or communication unitsKE, which are each connected to the Ethernet switch SW situated in thecentral module ZBG, are likewise situated in the central communicationdevice ZBG. All communication units KE have their own addressinformation mac1_1 . . . k_n, macz1 . . . 1—also called a MAC address(Medium Access Control)—which uniquely identifies the respectivecommunication unit KE in the packet-oriented communications network EN.Each communication device DBG1 . . . k, ZBG that is connected to thepacket-oriented communications network EN has a control device STE,which is connected to the components of the respective communicationdevice—and therefore to the respective transformer modules KE and theEthernet switch SW. The transformer modules KE situated in the centralcommunication device ZBG each have a connection AL, via which therespective transformer modules KE are connected to the higher-levelcommunications network OKN that is configured—in this exemplaryembodiment—according to the ISDN transmission method, via correspondingoutputs UL in the central communication device ZBG.

According to an alternative development version illustrated in FIG. 2,the outputs AL of the transformer modules KE situated in the centralcommunication device ZBG are taken back to corresponding ports AP′ ofthe Ethernet switch SW situated in the central module ZBG, said Ethernetswitch SW being connected to the higher-level communications network OKNvia further ports AP″. The corresponding configuration transmitsinformation between the transformer modules (KE) and the higher-levelcommunications network (OKN) via the Ethernet switch SW and itsconnections AP′, AP″ respectively.

When the arrangement illustrated in the block circuit diagram is startedup, communication relationships or logical point-to-point connections,via which the payload information is transmitted following successfulstartup, are to be set up between the communication units KE situated inthe remote and central communication devices.

The sequence of the inventive method is described in greater detailbelow:

-   1. In one development version of the inventive method, a freely    selectable MAC address iadr—hereinafter also called the    initialization address—is defined as being known to all control    units STE situated in the respective remote and central    communication devices DBG1 . . . k, ZBG. The time of initialization    of the communication arrangement illustrated in the block circuit    diagram, also called the system start-up or boot, is considered    below. After the initialization of the system or of the    communication arrangement, all communication devices DBG1 . . . k,    ZBG connected to the packet-oriented communications network EN    behave passively. For the exemplary embodiment, it may also be    assumed that—during the system initialization—a communication    relationship or logical point-to-point connection kb (many such    connections are signified in the block circuit diagram by a dotted    double-ended arrow) is to be set up between the transformer module    KE situated in the first communication device DBG1 and a transformer    module KE situated in the central communication device ZBG.-   2. The control device STE situated in the first remote communication    device DGB1 configures the initialization address iadr as a    (temporary) destination MAC address in the communication unit KE    assigned to said device. This initialization address iadr is also    configured in the assigned Ethernet switch in such a way that the    connection port AP that implements the connection to the    communications network EN is selected on the network side by said    initialization address iadr. Furthermore, all units situated in the    communications network EN, such as—for example—switches, are    configured by presetting them so that the data packets or Ethernet    frames having the initialization address iadr are switched toward    the central communication device.-   3. The control unit STE situated in the central communication device    ZBG configures the initialization address iadr in the relevant    Ethernet switch SW as pertaining to precisely one respective output    port AP assigned to precisely one transformer module KE, so that a    unique switching decision can be made immediately without “flooding”    or “learning”. Two development versions are possible according to    this exemplary embodiment: firstly, an incoming data packet or    Ethernet frame that has the initialization address iadr as the    destination address is switched via the transformer module KE and    via an interface to the control unit STE, said interface being    provided for this purpose, as indicated in the block circuit diagram    by the route L1, L2. In the other version, an Ethernet frame having    the initialization address iadr is switched via an interface of the    Ethernet switch SW—said interface being specially provided for this    purpose—directly to the control unit STE—as indicated in the block    circuit diagram by the route L3.-   4. After the initialization according to step 2, the transformer    module KE in the first remote communication device DBG1 starts to    transmit special data packets or Ethernet frames—illustrated    schematically in the block circuit diagram by a data packet    fr_z—cyclically to the initialization address iadr. These Ethernet    frames fr_z may, for example, be configured such that they differ    somehow from a normal payload and can therefore be clearly    identified as a “handshake”. This may be achieved, for example, by    setting a specific value of the “Ethernet type field” defined in the    Ethernet standard. Unlike the values already provided or reserved in    the standard, this value may be freely selected. Furthermore, the    MAC address—in this case mac1_1—of the transformer module KE is    inserted in the generated Ethernet frames fr_z as the “originating    address”.-   5. The Ethernet switch SW situated in the first remote communication    device DGB1 forwards the data packet fr_z thus generated to the    Ethernet EN via the connection port AP, since this switching    decision is clear as a result of step 2.-   6. The data packet fr_z switched to the central module ZBG via the    communications network EN is received by the Ethernet switch SW    situated in the central communication device ZBG, whereby the    originating address mac1_1 contained in the received data packet    fr_z is identified or “learnt” and a unique switching decision is    likewise made by the Ethernet switch SW on the basis of the    configuration described in step 3. The received data packet is    forwarded to the control device STE of the central communication    device ZBG via one of the configured connection ports AP, either via    the illustrated route L1, L2 or via the alternative route L3,    depending on the version selected.-   7. The control device STE situated in the central communication    device ZBG extracts from the received data packet or Ethernet frame    fr_z the originating MAC address (in this case mac1_1) contained in    it, and selects a transformer module KE that is currently unassigned    and available in the central communication device ZBG. For this    exemplary embodiment it must be assumed that the transformer module    KE with the corresponding MAC address macz1 is selected. The control    device STE implements the extracted originating MAC address (mac1_1)    in the selected transformer module KE (macz1) as the destination for    the transmit direction of the point-to-point connection to be set    up. The control device STE also determines the MAC address of the    selected transformer module (in this case macz1), which in turn must    be communicated to the first remote communication device DBG1 as the    (ultimate) destination.-   8. The control device STE situated in the central communication    device ZBG generates (for example via the route L3 illustrated in    the block circuit diagram) an equally “special” Ethernet frame as    the response to the Ethernet frame emitted by the remote    communication device DBG1. The destination of this special Ethernet    frame or data packet schematically illustrated in the block circuit    diagram by a data packet fr_d—is the first remote communication    device DBG1, or the communication unit or transformer module KE    (mac1_1) assigned to said remote communication device DBG1—i.e. the    MAC address mac1_1 that has just been learnt is inserted in the    generated Ethernet frame fr_d as destination information.    Furthermore, the originating MAC address of the transformer module    (in this case macz1) selected in step 7 is inserted in the special    Ethernet frame fr_d as the originating address. All Ethernet    switches SW affected have learnt the MAC address of the transformer    module KE assigned to the first remote communication device DBG1 and    are able to make a unique switching decision for the return route.-   9. The Ethernet switch SW situated in the first remote communication    device DBG1 extracts from this received data packet or response    Ethernet frame fr_d in a similar way to step 3. In this way the    control device STE can extract the originating MAC address contained    in the Ethernet frame and configure it as the ultimate destination    of the point-to-point connection kb to be set up or configured in    the transformer module KE assigned to it.-   10. The transformer module KE situated in the first remote    communication device DGB1 stops the cyclical emission of Ethernet    frames fr_z according to step 4, so that the transportation of the    actual payload via the communication device kb, that was set up with    the aid of the inventive method, may now commence.

According to an alternative development version of the communicationarrangement illustrated in the block circuit diagram, the respectiveremote communication devices DBG1 . . . k can each be connected to thecentral communication device ZBG via a connection line implementing thecommunications network EN, said connection line VL being indicated inthe block circuit diagram by a dotted line. All data packets emitted bythe remote communication devices DBG1 . . . k are automatically switchedor routed to the central communication device ZBG via these connectionlines VL. It should be noted that the random MAC address orinitialization address iadr previously provided for the inventive methodis not required in an arrangement of this type, since all data packetsare switched or transmitted to the central communication device ZBG fromthe remote communication devices DBG1 . . . k via the connection lineswithout switching decisions, and therefore the initialization address isnot required as destination information or routing information for theEthernet frames. In this development version, therefore, only the MACaddresses of the respective transformer modules KE that represent theend points of the point-to-point connections to be set up—i.e. mac1_1 .. . k_n, macz1 . . . 1—are inserted and transmitted in the describedway. The non-use of routing information in Ethernet frames would not,however, conform to the standard (e.g. as per IEEE 802.3), which meansthat the inventive method could not be implemented withstandard-compliant components. A proprietary adaptation—which isassociated with higher cost—would be required, while it is neverthelesspossible, in this development version, to dispense with any type ofmanagement (central or remote).

The inventive method enables a system configuration to be configured andbooted up dynamically without the involvement of a central managementsystem. The method described in greater detail in the exemplaryembodiment uses only resources that comply with the Ethernet standardand manages without broadcasts, which—for reasons of clear dataseparation—is regarded as unsuitable, particularly in the context ofcommunications networks being operated by different network operators.With the exception of the development version described above, theinventive method requires a unique MAC address or initializationaddress, which is fixed yet freely selectable, in order to configure anessentially unlimited quantity of point-to-point connections.

1-11. (canceled)
 12. A method for configuring communicationrelationships between communication units arranged in a packet-orientedcommunications network, wherein the communications units are assigned toa remote and a central communication device, and wherein eachcommunication unit has a communications-network-specific addressinformation, the method comprising: generating a data packet by theremote communication device or by a communication unit assigned to theremote communication device, wherein the data packet comprises theaddress information of the communication unit; transmitting the datapacket to the central communication device via the communicationsnetwork; identifying the address information included in the data packetby the central communication device; selecting a communication unitassigned to the central communication device by the centralcommunication device; assigning the identified address information tothe selected communication unit by the central communication device;generating a further data packet by the central communication device orthe selected communication unit, wherein the further data packetcomprises the address information of the selected communication unit;transmitting the further data packet to the remote communication devicevia the communications network by the central communication device orthe selected communication unit; and configuring the communicationrelationship between the communication unit assigned to the remotecommunication device and the selected communication unit via thecommunications network based on the address information included in thedata packet and the further data packet.
 13. The method according toclaim 12, wherein an initialization address that uniquely addresses thecentral communication device in the communications network is provided,wherein the initialization address is inserted as destinationinformation in the data packet to be transmitted to the centralcommunication device, and wherein the data packet is switched via thecommunications network to the central communication device with the helpof the inserted initialization address.
 14. The method according toclaim 12, wherein the address information that is identified and isassigned to the selected communication unit is inserted as destinationinformation in the further data packet to be transmitted to the remotecommunication device, and wherein the further data packet is switchedvia the communications network to the remote communication device withthe help of the inserted address information.
 15. The method accordingto claim 13, wherein the address information that is identified and isassigned to the selected communication unit is inserted as destinationinformation in the further data packet to be transmitted to the remotecommunication device, and wherein the further data packet is switchedvia the communications network to the remote communication device withthe help of the inserted address information.
 16. The method accordingto claim 12, wherein the address information of the selectedcommunication unit is inserted as the originating address in the furtherdata packet to be transmitted to the remote communication device. 17.The method according to claim 13, wherein the address information of theselected communication unit is inserted as the originating address inthe further data packet to be transmitted to the remote communicationdevice.
 18. The method according to claim 14, wherein the addressinformation of the selected communication unit is inserted as theoriginating address in the further data packet to be transmitted to theremote communication device.
 19. The method according to claim 12,wherein the remote communication device is connected to the centralcommunication device via at least one connection line implementing thecommunications network.
 20. The method according to claim 13, whereinthe remote communication device is connected to the centralcommunication device via at least one connection line implementing thecommunications network.
 21. The method according to claim 14, whereinthe remote communication device is connected to the centralcommunication device via at least one connection line implementing thecommunications network.
 22. The method according to claim 16, whereinthe remote communication device is connected to the centralcommunication device via at least one connection line implementing thecommunications network.
 23. The method according to claim 12, whereinthe communications network is configured as a frame-oriented orpacket-oriented communications network according to IEEE standard IEEE802.3.
 24. The method according to claim 12, wherein the centralcommunication device and the remote communication device each comprisesa switching unit configured according to IEEE standard 802.3, via whichthe communication units that are respectively assigned to thecommunication devices are connected to the communications network. 25.The method according to claim 12, wherein the configured communicationrelationship comprises one or more logical point-to-point connections.26. A communication arrangement for the configuration of communicationrelationships between communication units situated in a packet-orientedcommunications network and assigned to at least one remote communicationdevice and one central communication device, wherein each of thecommunication units has communications-network-specific addressinformation, wherein the at least one remote communication device or atleast one communication unit assigned to the remote communicationdevice, comprises first mechanisms for generating at least one datapacket having the address information of the respective communicationunit, and for forwarding the at least one generated data packet to thecommunications network, and wherein the central communication deviceand/or at least one communication unit assigned to the centralcommunication device comprises second mechanisms for identifying theaddress information contained in at least one received data packet, andfor selecting at least one communication unit assigned to the centralcommunication device, and for assigning the identified addressinformation to the selected communication unit, and for generating atleast one further data packet having the address information of therespective selected communication unit, and for transferring thegenerated further data packet to the at least one remote communicationdevice via the communications network, and wherein the first and secondmechanisms are configured such that, with the aid of the addressinformation transmitted to the central and the remote communicationdevice, the communication relationship between the communication unitassigned to the remote communication device and the selectedcommunication unit is configured via the communications network.
 27. Thecommunication arrangement according to claim 26, wherein the at leastone remote communication device, the central communication device, andthe communications network are part of a network device arrangeable in ahigher-level or superordinate communications network.
 28. Thecommunication arrangement according to claim 27, wherein the at leastone remote communication device and the central communication device areconfigured as modules situated in the network device.
 29. A method forthe configuration of communication relationships between communicationunits situated in a packet-oriented communications network, saidcommunications units being assigned to at least one remote communicationdevice and to one central communication device and each havingcommunications-network-specific address information, the methodcomprising: generating a first data packet comprising an addressinformation of a communication unit assigned to the remote communicationdevice by the remote communication device or by the communication unitassigned to the remote communication device; transmitting the first datapacket to the central communication device via the communicationsnetwork; identifying the address information, selecting at least onecommunication unit assigned to the central communication device, andassigning the identified address information to the selected at leastone communication unit, by the central communication device; andgenerating a second data packet comprising an address information of theselected communication unit, and transmitting the second data packet tothe at least one remote communication device via the communicationsnetwork, by the central communication device or the at least oneselected communication unit, wherein a communication relationshipbetween the communication unit assigned to the remote communicationdevice and the selected communication unit is configured via thecommunications network based on the address information transmitted tothe central and the at least one remote communication device.